I’m thinking of a bullet through the sleeve scenario. Or, if you make a ring with thumb and finger, and fire a bullet through that. Would you get injured? Is there a shockwave/ring of fire/plasma/vortex surrounding the bullet?
I can’t see how that could happend. How would such a injury manifest itself? Even something heavy like a .50 cal bullett just out of the barell, would still have a fairly insignificant energy as compared to, say, a car passing you very close at highway speeds. (Which, I know from personal experience, won’t injury me in any way except if the drag of the air vortex following the car drags me into the road for the next car to hit me 
)
There is a shockwave around the bullett as it passes the sound barrier, (which is why it goes crack), but from such a tiny mass it couldn’t possible create enough force to injure someone.
ETA: Not a ballistics tpye guy at all, so I am sure the next answer will tell me I’m completely wrong
I’ll provide a quick anecdote (and it’s just an anecdote) while waiting for a more scientific answer. You may remember years back (80s) when some people with rifles were firing from an elevated cliff in Mexico across the Rio Grande down onto the US side at hikers, rafters, etc. This happened several times, one or more people were killed and they eventually caught and tried the culprits.
A geology department classmate of mine was in one of the targeted groups and was pinned down for hours behind some boulders until dark when he and his group could escape. In the initial volley one of the bullets passed through his shirt breast pocket as it hung, albeit extremely close, to his body. I’m assuming then that a large caliber bullet traveling at near maximum velocity passed within a few inches of him near center mass but it did him no harm whatsoever, aside from the realization of just how close he had come to being terminally perforated. YNBEMV.
near bullet experience
If a supersonic bullet passes close to your ears, you might intensely dislike the experience and lose some hearing.
I think there’s a shockwave not just when a bullet passes the sound barrier but through all of its supersonic trajectory. I don’t know if that small shockwave is enough to injure something other than ears.
Yes. Anytime an object is moving through a fluid medium faster than the speed of sound, there will be a shock wave.
Does the shockwave reduce in intensity by the square or the cube of the distance?
In bootcamp during shooting practice, part of the group would sit under the targets with a few meters of earth and concrete above us between us and the targets. After going through the targets, the bullets ended their trajectory in earthworks about 10 meters away from us.
After about 50 rounds, my ears hurt. It must be pretty bad to have it go right next to your ear, especially if the shockwave loses intensity at the cube of distance.
I thought it might be surrounded by hot air that may burn you. Or if the body had a long enough tube and the bullet passed through it, the pressure produced may cause some damage? Which is why rifle barrels need to be carefully made.
A shockwave, yes, but I don’t remember John Wayne shooting fireballs in all those documentaries.
Do I understand correctly your post to the effect that the bullet going through the barrel creates high pressure?
It’s the other way around. The high pressure from the burning powder (which turns into expanding gas) propels the bullet through the barrel like a shaken up champagne bottle propels its cork.
Perhaps the bullet travelling through the air creates significant pressure but that’s unlikely to have much effect on barrel design.
The shock wave is composed of air that has been adiabatically compressed, and so it will be warm, or even hot, depending on how fast the object is moving. But the object moves past so quickly that the warm/hot shock wave will only be incident on your skin for a fraction of a second, not enough time to heat it appreciably.
The fast-moving object itself, however, may exist inside that shock wave for prolonged periods and can get pretty warm. The skin of the Concorde (which cruised at Mach 2) reached a couple hundred degrees near the nose. The skin of the SR-71 (which cruised at Mach 3) got even hotter. Spacecraft reentering the earth’s atmosphere (at roughly Mach 20) experience temperatures of thousands of degrees.
a high-speed bullet traveling at Mach 2+ would have a shock wave with a temperature of a couple hundred degrees, but its time-of-flight would be so short - just a second or two - that the bullet itself would not heat appreciably from the shock wave.
I could easily see hearing damage. I have had bullets (accidentally) whiz by me in relative close proximity and the noise was appreciable. It had somewhat of a stunning effect. I can understand why they train soldiers to get used to live rounds going overhead.
We’ve read enough soldiers’ accounts of bullets zinging past them. Hiroo Onoda dodged a carbine bullet by twisting his body (it was nightime and he actually saw the bullet coming at him, carbine slugs are slow.)
What about a larger projectile? I’m thinking anything between the largest held firearms and a Schwerer Gustav shell. If terminology matters, the OP was about bullets. Is a 7.1 tonne shell still a bullet? How about a Rod from God?
WHOAH!
I have noting to add about the thread but what was this story (the Mexicans shooting into US not the guy in your story as such)? Does it have a wikipedia article (daft as that sounds) that you can link me to?
I’ve read references (and will try to find some) to people being killed when cannonballs (of the old-fashioned gunpowder smoothbore Napoleonic era) flew closely past them.
Hm… Searching isn’t doing any good. I find claims that, yes, a near miss from a cannonball can harm or kill…and other claims that this is a myth and has been debunked.
I also find claims that flying splinters doing harm in naval battles is a myth and has been debunked, and I thought that one was on very secure ground!
:dubious: I would think this depends greatly on one’s definition of “splinter.” If a splinter is something the size of a pencil lead, then no, I wouldn’t expect much of a problem - but if “splinter” refers to a chunk of wood the size of a beer mug, then yes, I would expect there is a potential for fatal injuries - not from shock waves or anything like that, but from direct kinetic impact.
You would need to know the overpressure that is generated by a bullet or shell that is supersonic.
Here is a point of reference from NASA:
Overpressure
Sonic booms are measured in pounds per square foot of overpressure. This is the amount of the increase over the normal atmospheric pressure which surrounds us (2,116 psf/14.7 psi).
At one pound overpressure, no damage to structures would be expected.
Overpressures of 1 to 2 pounds are produced by supersonic aircraft flying at normal operating altitudes. Some public reaction could be expected between 1.5 and 2 pounds.
Rare minor damage may occur with 2 to 5 pounds overpressure.
As overpressure increases, the likelihood of structural damage and stronger public reaction also increases. Tests, however, have shown that structures in good condition have been undamaged by overpressures of up to 11 pounds.
Sonic booms produced by aircraft flying supersonic at altitudes of less than 100 feet, creating between 20 and 144 pounds overpressure, have been experienced by humans without injury.
Damage to eardrums can be expected when overpressures reach 720 pounds. Overpressures of 2160 pounds would have to be generated to produce lung damage.
So supersonic aircraft have flown over humans within less than 100 feet with no injury, but overpressures decrease with distance. Without remarking on any of the anecdotal evidence above, I could image that a decent sized supersonic bullet passing 1/2 inch away might be enough to produce light local damage.
But truthfully, I have no idea. We need a ballistics/aerodynamics/overpressue expert!
I just checked, and Theodore Roosevelt refers to casualties from splinters (yes, the larger kind!) in “The Naval War of 1812.” I figure he knows what he’s talking about!
I doubt that’s possible, they aren’t * that *slow. More likely the bullet was going to barely miss anyway and he just thought the twist saved him
If the bullet is fired close by, then there is a lot of damage caused by the discharge from the barrel. I knew a guy that lost part of face that way even though the bullet missed him.